Medical Records, Billing Info Key to Michael Jackson Case

Myriad questions and numerous individuals are at the center of the Michael Jackson investigation, but there may be one central key to uncovering the truth.

Drs. Conrad Murray, Arnold Klein, Allan Metzger and others have come under suspicion as officials try to determine who supplied and administered the anesthesia Propofol and other drugs to the late star. But details so far have been sketchy.

When dealing with celebrities, some doctors use pseudonyms for patients and sometimes their medical records and charts mysteriously get "lost."

But TMZ reports that most doctors leave one indelible footprint when it comes to treating their patients, and it all starts with billing information.

Many doctors use medical software systems from MD Systems, NexTech and others. These companies provide software in which doctors input billing data.

Doctors typically input the patient's name, billing amount, the type of treatment, type of drugs prescribed and administered, and the date of service.

The clincher? That data cannot be deleted from the server.

The system allows doctors to add other data like medical charts, which can be deleted. But if someone deletes data, the software shows the name of the user who did it in addition to the date it took place. Basic billing information will not go away.

The police found Propofol - a powerful anesthesia that should never be outside a hospital - in Jackson's house. If cops find who supplied and administered it, the doctor(s) could face very serious questions and possibly even criminal charges.

Hilary Duff to Guest Star on Gossip Girl

Is the Upper East Side ready for more star power? We'll find out as Hilary Duff is coming to Gossip Girl for a guest role this fall, according to Entertainment Weekly.

The actress-designer-pop singer will play Olivia Burke, a movie star (typecasting lives) who enrolls at NYU in search of the traditional college experience.

Her character will room with the unpopular Vanessa (Jessica Szohr) at the college. Duff will debut in this season's fourth episode, slated to air October 5.

Gossip Girl producers spotted an opening in Duff's schedule after NBC passed on her comedy pilot Barely Legal. She was to play a lawyer in it, of course.